Drag and drop the Exported messages, from the flash drive, to the Desktop.
Open Outlook Express.
Open the Inbox, drag one message from the Exported messages, into the Inbox, and drop it.
I always use the Right pane of Outlook Express, so I don't have to zero in on one tiny folder.

The message should appear in Outlook Express as soon as you drop it.

Then create folders as needed in Outlook Express, access each folder and drag those messages that you want into those folders.

It is not going to be as easy as simply Importing and clicking a few buttons.

Alternatively, if you click on one of the Exported messages (outside of Outlook Express), it should open as if it was in Outlook Express.

U can take backup of windows mail. open windows mail go to file and export the items to a back up drive.
or
right click on windows mail and go to properties and select the path shown there.
now click windows+r and paste the path copied and press enter

now it will take u to the windows mail data. copy it and take back up on to external drive....

now u can install incredi mail and use import export option under file tab and load ur mails. its simple in incerdimail to import n export as they r just user friendly options.